[en] This study investigates interlaminar fracture characteristics of Graphite/ Epoxy composite(HFG Graphite/Epoxy) under model I (opening mode), Mode II (sliding mode) and mixed mode loading conditions. The effects on interlaminar fracture toughness due to different fiber orientations on the crack surface are also investigated. The antisymmetric test fixture proposed by M. Arcan is used for this test. Both critical stress intensity factors and critical energy release rates were determined and several mixed mode fracture criteria were compared to the experimental data. Also fracture surfaces were investigated to obtain informations on the fracture behaviors of Graphite/Epoxy composite by means of a scanning electron microscope(SEM). (Author)